EP0749025A1 - Procédé de fabrication d'un coupleur à fibre optique - Google Patents

Procédé de fabrication d'un coupleur à fibre optique Download PDF

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Publication number
EP0749025A1
EP0749025A1 EP96110178A EP96110178A EP0749025A1 EP 0749025 A1 EP0749025 A1 EP 0749025A1 EP 96110178 A EP96110178 A EP 96110178A EP 96110178 A EP96110178 A EP 96110178A EP 0749025 A1 EP0749025 A1 EP 0749025A1
Authority
EP
European Patent Office
Prior art keywords
optical fiber
optical fibers
fibers
optical
fiber coupler
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Granted
Application number
EP96110178A
Other languages
German (de)
English (en)
Other versions
EP0749025B1 (fr
Inventor
Hiroshi Yokohama Works Of Sumitomo Suganuma
Tomoyuki Yokohama Works Of Sumitomo Hattori
Hiroaki Yokohama Works Of Sumitomo Takimoto
Yoshiharu Yokohama Works of Sumitomo Okawa
Hiroshi Yokohama Works of Sumitomo Yokota
Kazuhiko Sumiden Opcom Ltd. Arimoto
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Sumiden Opcom Ltd
Sumitomo Electric Industries Ltd
Original Assignee
Sumiden Opcom Ltd
Sumitomo Electric Industries Ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Priority claimed from JP17187691A external-priority patent/JPH04368904A/ja
Priority claimed from JP18547591A external-priority patent/JPH0511133A/ja
Application filed by Sumiden Opcom Ltd, Sumitomo Electric Industries Ltd filed Critical Sumiden Opcom Ltd
Publication of EP0749025A1 publication Critical patent/EP0749025A1/fr
Application granted granted Critical
Publication of EP0749025B1 publication Critical patent/EP0749025B1/fr
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

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Classifications

    • G—PHYSICS
    • G02—OPTICS
    • G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
    • G02B6/00—Light guides; Structural details of arrangements comprising light guides and other optical elements, e.g. couplings
    • G02B6/24—Coupling light guides
    • G02B6/26—Optical coupling means
    • G02B6/28—Optical coupling means having data bus means, i.e. plural waveguides interconnected and providing an inherently bidirectional system by mixing and splitting signals
    • G02B6/2804—Optical coupling means having data bus means, i.e. plural waveguides interconnected and providing an inherently bidirectional system by mixing and splitting signals forming multipart couplers without wavelength selective elements, e.g. "T" couplers, star couplers
    • G02B6/2856—Optical coupling means having data bus means, i.e. plural waveguides interconnected and providing an inherently bidirectional system by mixing and splitting signals forming multipart couplers without wavelength selective elements, e.g. "T" couplers, star couplers formed or shaped by thermal heating means, e.g. splitting, branching and/or combining elements
    • G—PHYSICS
    • G02—OPTICS
    • G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
    • G02B6/00—Light guides; Structural details of arrangements comprising light guides and other optical elements, e.g. couplings
    • G02B6/24—Coupling light guides
    • G02B6/26—Optical coupling means
    • G02B6/28—Optical coupling means having data bus means, i.e. plural waveguides interconnected and providing an inherently bidirectional system by mixing and splitting signals
    • G02B6/2804—Optical coupling means having data bus means, i.e. plural waveguides interconnected and providing an inherently bidirectional system by mixing and splitting signals forming multipart couplers without wavelength selective elements, e.g. "T" couplers, star couplers
    • G02B6/2821—Optical coupling means having data bus means, i.e. plural waveguides interconnected and providing an inherently bidirectional system by mixing and splitting signals forming multipart couplers without wavelength selective elements, e.g. "T" couplers, star couplers using lateral coupling between contiguous fibres to split or combine optical signals
    • G02B6/2835—Optical coupling means having data bus means, i.e. plural waveguides interconnected and providing an inherently bidirectional system by mixing and splitting signals forming multipart couplers without wavelength selective elements, e.g. "T" couplers, star couplers using lateral coupling between contiguous fibres to split or combine optical signals formed or shaped by thermal treatment, e.g. couplers

Definitions

  • the present invention relates to a process for producing an optical fiber coupler according to the preamble of claim 1.
  • An optical fiber coupler is an optical component that permits light to be branched or coupled between a plurality of optical fibers.
  • Optical fiber couplers are known to be produced by either a melt drawing process or a polishing process. The melt drawing process is said to be best suited for the production of couplers of single-mode fibers (see “Recent Techniques on Optical Fiber Couplers” in Optronics, No. 5, p. 125, 1988). This process starts with stripping part of the coating from a plurality of optical fibers, heating them to fuse the stripped fibers together, forming a bundle by twisting the fibers or arranging them parallel to one another, drawing the bundle under heating until its characteristics such as branching ratio attain predetermined values, and forming a coupling portion.
  • optical fiber couplers One of the important applications of optical fiber couplers is in branching of optical communication lines.
  • light emitted at a plurality of wavelengths e,g., 1.31 ⁇ m and 1.55 ⁇ m
  • optical fiber couplers produced by the melt drawing process have the disadvantage that their branching ratio is largely wavelength dependent.
  • melt drawing optical fibers having different outside diameters on cladding see Takeuchi et al., "Broad Wavelength Range Optical Fiber Couplers 1" in C-207 of the Preprint for 1989 Autumn National Conference of the Institute of Electronics, Information and Communication Engineers) or by melt drawing optical fibers having different mode field diameters (see “Broad Wavelength Range Optical Fiber Couplers 2" in C-208 of the same preprint).
  • This process uses two optical fibers of identical structure, one of which is drawn preliminarily to a smaller diameter.
  • the process is shown schematically in FIGURE 6, in which numeral 21 refers to an optical fiber, 22a and 22b to a clamper, and 23 to a burner.
  • tension is applied to the fiber so that it is pulled in opposite directions indicated bv arrows 61 and 62 in FIGURE 6, whereby the bare portion is drawn as it is heated with the burner 23.
  • the diameter of the preliminarily drawn bare portion determines the branching ratio of the optical fiber coupler to be produced and, hence, it is important to draw the bare portion of the fiber with good control and high repeatability.
  • the preliminary drawing step involves so many variables in connection with the draw speed, draw length, etc. that it is difficult to attain identically drawn diameters with separate fibers.
  • the present invention was developed under these circumstances and has as an object to provide a process that is capable of producing a wide-band optical fiber coupler using optical fibers having identical structure, said process in particular being capable of producing a wide-band optical fiber coupler with high repeatability.
  • the process of the present invention for producing an optical fiber coupler includes preliminary heat treatment for a predetermined time of part of the optical fibers before a plurality of optical fibers are used together into a unitary portion.
  • the core forming glass is doped with an element such as Ge or P to provide a higher index, or the cladding glass is doped with an element such as F or B to provide a lower index.
  • an optical fiber doped in either the core or the cladding or both is heated at elevated temperature, the dopants will diffuse and the index profile changes as shown in FIGURE 2(B), causing a substantial change in the core diameter.
  • the same optical fiber can produce optical fibers with substantial differences in structure depending upon whether it is given a heat treatment or not. Therefore, if heat-treated optical fibers are combined with non heat-treated optical fibers, followed by melt drawing to form a coupling portion, an optical fiber coupler having a substantially constant branching ratio over a broad wavelength range can be produced.
  • the index profile shown in FIGURE 2(B) can be varied by adjusting the time or temperature for heating optical fibers. Hence, it is possible to control the branching ratio, which can be set at desired values without using a number of optical fibers with different core or cladding diameters.
  • the process according to the present invention for producing an optical fiber coupler also includes preliminary heat treatment of part of the optical fibers as they are fixed to produce an axial stress before a plurality of optical fibers are fused together into a unitary portion.
  • optical fiber couplers can be produced with a marked improvement in the consistency of branching ratio.
  • FIGURE 7 is a graph showing how the diameter of a heated portion of an optical fiber varies with time when it was heated with both ends being fixed under an axial stress of 1.6 kg/mm 2 . Since the diameter of the heated portion can be reduced to a desired smaller value by controlling the heating time, it is also possible to control the branching ratio, which can be set at desired values without using a number of optical fibers with different core or cladding diameters.
  • FIGURE 1 is a flow chart illustrating an example of the process for producing an optical fiber coupler in accordance with the present invention.
  • step 1 at least one of the optical fibers to be used is partially stripped of its coating.
  • step 2 the bare portion of the stripped optical fiber, or fibers, is heated for a predetermined time.
  • step 3 the other optical fibers which have not been heat-treated are stripped of the coating.
  • step 4 the bare portions of the optical fibers are heated as they are brought into intimate contact, thereby forming a unitary portion.
  • step 5 in which the unitary portion is drawn under heating until a predetermine branching ratio is attained.
  • step 6 the coupling portion of an optical fiber is formed. If desired, steps 4 and 5 can be performed simultaneously.
  • a sample of an optical fiber coupler was prepared for communications at a wavelength of 1.3 ⁇ m using two common single-mode optical fibers (cladding diameter 125 ⁇ m; core diameter 9 ⁇ m).
  • a propane/oxygen flame was used as a source for heating the opticai fibers.
  • one of the two optical fibers was stripped of the coating over a length of 40 mm and, thereafter, the bare portion of the fiber was heated for 1 minute with propane and oxygen being supplied at flow rates of 70 cc and 160 cc per minute, respectively.
  • the non heat-treated optical fiber was similarly stripped of the coating and the bare portions of the two optical fibers were heated for 30 seconds to fuse the fibers together as they were brought into intimate contact.
  • propane and oxygen were supplied at flow rates of 40 cc and 80 cc per minute, respectively.
  • the unitary portion was drawn by 8.5 mm on either side under heating to prepare an optical fiber coupler.
  • propane and oxygen were supplied at flow rates of 40 cc and 90 cc per minute, respectively.
  • the thus prepared optical fiber coupler had a branching ratio versus wavelength characteristic as shown in FIGURE 3, from which one can see that the coupler exhibited stable branching ratios of 50 ⁇ 5% over a broad wavelength range of from 1.2 ⁇ m to 1.7 ⁇ m.
  • FIGURE 4 is a flow chart illustrating an example of the process for producing an optical fiber coupler in accordance with the present invention.
  • step 41 at least one of the optical fibers to be used is partially stripped of the coating.
  • preheating is performed in step 42.
  • the bare portion of the optical fiber is heated as it is fixed in such a way so as to produce an axial stress.
  • step 43 the other optical fibers which have not been heat-treated are stripped of the coating.
  • step 44 the bare portions of the optical fibers are heated as they are brought into intimate contact, thereby forming a unitary portion.
  • step 45 the unitary portion is drawn under heating until a predetermined branching ratio is attained.
  • step 46 the coupling portion of an optical fiber coupler is formed. If desired, steps 44 and 45 can be performed simultaneously.
  • FIGURE 5 is a diagram showing the step of preliminary heating which is referred to as step 42 in the flow chart of FIGURE 4.
  • step 42 the components which are the same as those shown in FIGURE 6 are identified by like numerals and will not be described in detail.
  • the optical fiber 21, with part of its coating stripped, is gripped and fixed by clampers 22a and 22b on opposite sides of the bare portion as it is placed under an axial stress.
  • the bare portion of the fiber 21 is then heated with the burner 23 with the distance L between clampers 22a and 22b being kept constant.
  • a sample optical fiber coupler was prepared for communications at wavelength of 1.3 ⁇ m using two common single-mode optical fibers (cladding diameter 125 ⁇ m; core diameter 9 ⁇ m).
  • a propane/oxygen flame was used as a source for heating the optical fibers.
  • one of the two optical fibers was stripped of the center coating over a length of 40 mm and, thereafter, both ends of the bare portion of the fiber were fixed as it was placed under a stress of 1.6 kg/mm 2 . Under such conditions, the optical fiber was heated for 50 seconds with propane and oxygen being supplied at flow rates of 70 cc and 160 cc per minute, respectively.
  • the non heat-treated optical fiber was similarly stripped of the coating and the bare portions of the two optical fibers were heated to fuse together as they were brought into intimate contact.
  • propane and oxygen were supplied at flow rates of 40 cc and 80 cc per minute, respectively.
  • this unitary portion was drawn by 8.5 mm on either side under heating to prepare an optical fiber coupler.
  • optical fiber coupler The samples of optical fiber coupler were prepared by identical process and their characteristics were evaluated. Each sample was found to exhibit stable branching ratios of 50 ⁇ 5% over a broad wavelength range of from 1.2 ⁇ m to 1.7 ⁇ m.
  • FIGURE 8 illustrates an apparatus for developing a stress in the preheating step.
  • Reference number 21 is an optical fiber
  • 22a and 22b designate clampers, 24a and 24b an optical fiber gripper, 25 a slider, 26 a weight, 27 a string and 28 a pulley.
  • An end of the optical fiber 21 is fixed by the gripper 24a whereas the other end is secured by the gripper 24b supported on the slider 25.
  • the clampers 22a and 22b are yet to be activated.
  • the gripper 24b is connected to the string 27 which is attached to the weight 26 via the pulley 28, whereupon a tension is applied to the optical fiber 21, developing a stress in the bare portion of the fiber 21.
  • the fiber is fixed with the stress having developed in the bare portion. Once the fiber is clamped, it is no longer subject to the effect of the weight and, hence, it may be removed. In the examples above, the weight 26 weighed 20 g.
  • the present invention offers the advantage that an optical fiber coupler having stable branching ratios over a broad wavelength range can be produced with high repeatability without using optical fibers of special structures but using optical fibers of identical structure.

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  • Physics & Mathematics (AREA)
  • General Physics & Mathematics (AREA)
  • Optics & Photonics (AREA)
  • Mechanical Coupling Of Light Guides (AREA)
  • Optical Fibers, Optical Fiber Cores, And Optical Fiber Bundles (AREA)
EP96110178A 1991-06-18 1992-06-17 Procédé de fabrication d'un coupleur à fibre optique Expired - Lifetime EP0749025B1 (fr)

Applications Claiming Priority (7)

Application Number Priority Date Filing Date Title
JP17187691A JPH04368904A (ja) 1991-06-18 1991-06-18 光ファイバカプラの製造方法
JP17187691 1991-06-18
JP171876/91 1991-06-18
JP185475/91 1991-06-28
JP18547591A JPH0511133A (ja) 1991-06-28 1991-06-28 光フアイバカプラの製造方法
JP18547591 1991-06-28
EP92110256A EP0519440B1 (fr) 1991-06-18 1992-06-17 Procédé de fabrication d'un coupleur à fibre optique

Related Parent Applications (2)

Application Number Title Priority Date Filing Date
EP92110256A Division EP0519440B1 (fr) 1991-06-18 1992-06-17 Procédé de fabrication d'un coupleur à fibre optique
EP92110256.2 Division 1992-06-17

Publications (2)

Publication Number Publication Date
EP0749025A1 true EP0749025A1 (fr) 1996-12-18
EP0749025B1 EP0749025B1 (fr) 2000-05-24

Family

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Family Applications (2)

Application Number Title Priority Date Filing Date
EP96110178A Expired - Lifetime EP0749025B1 (fr) 1991-06-18 1992-06-17 Procédé de fabrication d'un coupleur à fibre optique
EP92110256A Expired - Lifetime EP0519440B1 (fr) 1991-06-18 1992-06-17 Procédé de fabrication d'un coupleur à fibre optique

Family Applications After (1)

Application Number Title Priority Date Filing Date
EP92110256A Expired - Lifetime EP0519440B1 (fr) 1991-06-18 1992-06-17 Procédé de fabrication d'un coupleur à fibre optique

Country Status (6)

Country Link
US (1) US5309536A (fr)
EP (2) EP0749025B1 (fr)
AU (1) AU653605B2 (fr)
CA (1) CA2071344C (fr)
DE (2) DE69223348T2 (fr)
ES (1) ES2109958T3 (fr)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP1219987A1 (fr) * 2000-12-28 2002-07-03 Sumitomo Electric Industries, Ltd. Procédé d'épissure de fibres optiques

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Publication number Priority date Publication date Assignee Title
DE4202931A1 (de) * 1992-02-01 1993-08-05 Kabelmetal Electro Gmbh Steckverbindung zwischen zwei lichtwellenleitern eines optischen kabels und verfahren zu ihrer herstellung
US5410626A (en) * 1992-06-25 1995-04-25 Kyocera Corporation Optical coupler having a tapered fused region
JPH06222242A (ja) * 1993-01-27 1994-08-12 Shin Etsu Chem Co Ltd 光ファイバカプラおよびその製造方法
JPH06224497A (ja) * 1993-01-27 1994-08-12 Shin Etsu Chem Co Ltd 光増幅器
JPH07253518A (ja) * 1994-03-15 1995-10-03 Fujitsu Ltd スターカプラの製造方法とスターカプラ
US5729643A (en) * 1996-04-05 1998-03-17 Coherent, Inc. Tapered composite optical fiber and method of making the same
DE19643661A1 (de) * 1996-10-22 1998-04-23 Siemens Ag Verfahren sowie Vorrichtung zur Bestimmung von Spleißparametern
US5852692A (en) * 1997-05-16 1998-12-22 Coherent, Inc. Tapered optical fiber delivery system for laser diode
US6481903B1 (en) 1998-08-07 2002-11-19 Tycom (U.S.) Inc. Optical fiber splice protector and method for applying same
US6152611A (en) * 1998-08-07 2000-11-28 Tyco Submarine Systems Ltd. Method and apparatus for providing a flexible splint splice
MX336679B (es) 2011-11-23 2016-01-27 Adc Telecommunications Inc Conector de fibra optica de multifibras.
RU2619816C2 (ru) 2012-02-07 2017-05-18 Тайко Электроникс Райхем Бвба Кабельное концевое устройство в сборе и способ крепления оптоволоконного кабеля к разъему
MX338237B (es) 2012-02-20 2016-04-08 Adc Telecommunications Inc Conector de fibra óptica, montaje de conector de fibra óptica y cable, y métodos de fabricación.
US8939654B2 (en) 2012-09-27 2015-01-27 Adc Telecommunications, Inc. Ruggedized multi-fiber fiber optic connector with sealed dust cap
US9720185B2 (en) 2014-05-23 2017-08-01 Commscope Technologies Llc Systems and method for processing optical cable assemblies
CN110028235B (zh) * 2019-03-01 2020-09-08 江苏永鼎股份有限公司 一种基于连熔石英套管的光纤预制棒及其制造方法

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EP0209998A2 (fr) * 1985-07-17 1987-01-28 Andrew Corporation Méthode de fabrication de connecteurs à fibres optiques et méthode d'accordage utilisant la diffusion
WO1987000934A1 (fr) * 1985-07-30 1987-02-12 British Telecommunications Public Limited Company Coupleurs a fibres optiques fusionnees
EP0293289A2 (fr) * 1987-05-21 1988-11-30 Amphenol Corporation Coupleur indépendant de la longueur d'onde et son procédé de fabrication
US4798438A (en) * 1986-10-15 1989-01-17 Gould Inc. Method of making a single-mode evanescent-wave coupler having reduced wavelength dependence
EP0418871A2 (fr) * 1989-09-20 1991-03-27 Japan Aviation Electronics Industry, Limited Coupleur à fibres optiques à large bande et méthode pour sa fabrication
EP0418872A2 (fr) * 1989-09-20 1991-03-27 Japan Aviation Electronics Industry, Limited Coupleur à fibres optiques à large bande et méthode pour sa fabrication
JPH03136010A (ja) * 1989-10-23 1991-06-10 Sumitomo Electric Ind Ltd 光カプラ及びその製造方法
EP0431311A2 (fr) * 1989-12-08 1991-06-12 Corning Incorporated Coupleur à fibre optique achromatique et son procédé de fabrication

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EP0209998A2 (fr) * 1985-07-17 1987-01-28 Andrew Corporation Méthode de fabrication de connecteurs à fibres optiques et méthode d'accordage utilisant la diffusion
WO1987000934A1 (fr) * 1985-07-30 1987-02-12 British Telecommunications Public Limited Company Coupleurs a fibres optiques fusionnees
US4798438A (en) * 1986-10-15 1989-01-17 Gould Inc. Method of making a single-mode evanescent-wave coupler having reduced wavelength dependence
EP0293289A2 (fr) * 1987-05-21 1988-11-30 Amphenol Corporation Coupleur indépendant de la longueur d'onde et son procédé de fabrication
EP0418871A2 (fr) * 1989-09-20 1991-03-27 Japan Aviation Electronics Industry, Limited Coupleur à fibres optiques à large bande et méthode pour sa fabrication
EP0418872A2 (fr) * 1989-09-20 1991-03-27 Japan Aviation Electronics Industry, Limited Coupleur à fibres optiques à large bande et méthode pour sa fabrication
JPH03136010A (ja) * 1989-10-23 1991-06-10 Sumitomo Electric Ind Ltd 光カプラ及びその製造方法
EP0431311A2 (fr) * 1989-12-08 1991-06-12 Corning Incorporated Coupleur à fibre optique achromatique et son procédé de fabrication

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Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP1219987A1 (fr) * 2000-12-28 2002-07-03 Sumitomo Electric Industries, Ltd. Procédé d'épissure de fibres optiques
US6729777B2 (en) 2000-12-28 2004-05-04 Sumitomo Electric Industries, Ltd. Optical fiber splicing method and optical transmission line

Also Published As

Publication number Publication date
EP0519440B1 (fr) 1997-12-03
DE69223348T2 (de) 1998-03-26
DE69231103T2 (de) 2000-09-21
EP0519440A2 (fr) 1992-12-23
AU1833192A (en) 1992-12-24
AU653605B2 (en) 1994-10-06
CA2071344C (fr) 1997-04-15
US5309536A (en) 1994-05-03
EP0749025B1 (fr) 2000-05-24
ES2109958T3 (es) 1998-02-01
EP0519440A3 (en) 1993-06-23
DE69231103D1 (de) 2000-06-29
CA2071344A1 (fr) 1992-12-19
DE69223348D1 (de) 1998-01-15

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